Electrophotographic composing device

ABSTRACT

A device for recording a plate indicia representing a number of copies to be printed by the plate is provided for an electrophotographic composing device. The indicia recording means consists of graduated scales and pointers or indicators and are recorded upon a plate together with the image of an original in a portion outside thereof. Irrespective of the magnification or reduction of the original, the dimensions of the indicia remain unchanged so that the detection of indicia may be precisely made. Furthermore, undesired markings other than indicia may be positively prevented.

United States Patent Koizumi [451 Sept. 26, 1972 [54] ELECTROPHOTOGRAPHIC 3,111,887 11/1963 Alexander ..95/l.1

COMPOSING DEVICE Primary Examiner-John M. Horan [72] Inventor Yuuka Kolzumi Yokohama Japan Attorney-Henry T. Burke, Robert Scobey, Robert S. [73] Assignee: Ricoh Co., Ltd., Tokyo, Japan Cunham, P. E. Henninger, Lester W. Clark, Gerald W. Griffin, Thomas F. Moran, R. Bradlee Boal and [22] Filed Sept 1970 Christopher C. Dunham [21] Appl. No.: 70,129

[57] ABSTRACT [30] Foreign Application Priority Data A device for recording a plate indicia representing a number of copies to be printed by the plate is pro- Sept. 9, 1969 Japan ..44/70986 vided for an electrophotographic composing device. [52] Us Cl 95/11 The indicia recording means consists of graduated [51] To l7/2.4 Scales and pointers or indicators and are recorded upon a plate together with the image of an original in [58] Field of Search ..95/ 1.1, 355/14 8 portion outside thereofi Irrespective of the g cation or reduction of the original, the dimensions of [56] Reerences the indicia remain unchanged so that the detection of UNITED STATES PATENTS indicia may be precisely made. Furthermore, un-

desired markings other than indicia may be positively 2,958,269 11/1960 Sim ian ..95/1.l prevented 3,409,359 11/1968 Mullan ..95/l.1 X 3,356,000 12/1967 Marion ..95/1.1 4 Claims, 4 Drawing Figures PATENTEBSM IQR H 3.693.514

SHEET 1 OF 3 INVENTOR. YUM/64 KO/ZUM/ ATTO/Q/VFY 2 FIG. 4

INVENTOR- YUTAA A KO/ZU/V/ BY fl p ELECTROPI'IOTOGRAPHIC COMPOSING DEVICE BACKGROUND OF THE INVENTION The present invention relates to an electrophotographic composing device for producing a plate for offset printing press and more particularly a device to be incorporated in the composing device of the type described for recording upon a plate indicia representing a number of copies to be printed by said plate.

The present invention represents an improvement over the device disclosed in U.S. Pat. application Ser. No. 755 ,625 filed on Aug. 27, 1968, now abandoned by Tamaki Kaneko, entitled by Printing Plate.

In the pending application, Ser. No. 755,625 filed on Aug. 27, I968 the applicant proposed a method for recording upon a plate indicia representing a number of copies to be printed by the plate produced by the electrophotographic composing machine.

These indicia may be read mechanically, electrically or optically by a detector when the plate is mounted in an off-set printing press so that a desired number of copies may be automatically printed by the press. The indicia maybe black-colored marks or punched holes. In the former case, a black-colored mark may be so placed as to indicate a desired graduated scale mark to represent thereby a desired number of copies to be printed. These indicia consisting of the black-colored mark or dot and the graduated scale marks are placed upon a transparent original holder so that when the light image of an original is projected upon a photosensitive member, which is made into a plate for off-set printing presses, they may be also projected upon the plate.

However, in case of an electrophotographic composing device of the type in which an original is magnified or reduced on the electrophoto-sensitive member through a movable optical system, the indicia placed upon the original holder are also magnified or reduced in scale on the electrophoto-sensitive member accordingly. However, the detectors in the printing presses cannot detect these indicia on the plates when they are varied in dimensions. i Furthermore when the dusts or the like on the transparent original holder are recorded with-the indicia, theymay be picked up by the detectors, so that the noise is involved in the signals representing a desired number of copies to be printed by the plate.

SUMMARY OF THE INVENTION It is therefore one of the objects of the present invention to provide an improved device for use with the electrophotographic composing devices for recording upon a plate indicia representing a desired number of copies to be printed by said plate in such a manner that the dimensions of these indicia may remain unchanged irrespective of the magnification or reduction of an original.

It is another object of the present invention to provide the device of the type described whose indicia forming elements are not placed on an transparent original holder so that no dust or the like is recorded with these indicia, thereby eliminating the noise.

It is another object of the present invention to provide the device of the type described in which a member for supporting the indicia forming elements is not projected and recorded upon a plate.

According to one aspect of the present invention, the indicia forming elements to be projected upon a plate are disposed immediately above along a portion of the plate which is not used in printing so that no dust or the like is recorded upon the plate. These indicia forming elements are projected by a light source different from a light source for projecting the light image of the original upon the plate or photosensitive member so that the shadow of a member for supporting these indicia forming elements would be formed upon the plate.

However, according to another aspect of the present invention, both of the light sources are so arranged that the shadow formed by the light source for projecting the indicia forming elements may be illuminated by the beam of light from the light source for projecting the light image of the original whereby no shadow of the supporting member is formed upon the plate.

The present invention will become more apparent from the following description of the preferred embodiment thereof taken conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a diagrammatic sectional view of an em bodiment of an electrophotographic composing device of the present invention;

FIG. 2 is a top view of an exposure station illustrating an indicia recording device in accordance with the present invention;

FIG. 3 is a fragmentary view illustrating graduated scale mark forming elements and an indicator thereof; and

FIG. 4 is a diagrammatic view illustrating an arrangement for eliminating the shadow of an indicia forming element supporting member.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates an electrophotographic composing device 1 embodying the present invention. A electrophoto-sensitive member fed into the device 1 by an automatic sheet feeder 2 is uniformly charged in a charging station 3 and forwarded to an exposure station 6 by a conveyor belt 5 under the attracting force produced by a suction box 4. The electrophoto-sensitive member is held stationary in the exposure station during exposure inwhich a light source 7 is turned on, so that the beam of light is reflected by a reflecting mirror 8 and reaches an original placed upon a transparent original holder 9. The beam of light is ten reflected by the original and redirected by a reflecting mirror 10 and a movable optical system 11 toward the exposure station 6 so that the light image of the original is focused upon the electrophoto-sensitive member which is held stationary under the attracting force produced by the suction box 4. After exposure, the exposed paper is forwarded to a dry developing station 12 by the conveyor belt 5 and the electrostatic latent image is developed. Next the developed paper is forwarded to a fixing station 13 where it is fixed by heat and then discharged out of the device 1.

Referring to FIG. 2, the conveyor belt 5 consists of a plurality of belts 14 spaced apart laterally by a suitable distance and a plurality of small holes 15 formed through the top of the suction box 4 are so arranged as to be exposed between the spacings of the belts 14.

Graduated scale forming elements 16 and indicators 17 are located along on side edge of the conveyor belt 5. The graduated scale forming elements 16 comprise plurality of opaque comb-tooth-like members and are extended horizontally from an upstanding member 19 (See FIG. 3), which in turn is securely fixed to a device frame 18. Each unit of said graduated scale forming elements comprises a group of ten comb-tooth-like members. The indicators 17 comprise tapered plates and are slidably carried by a guide rod 20 which in turn is also securely fixed to the machine frame 18, so that an operator may slide the indicators 17 from the exterior of the composing device 1. That is, the indicators 17 are placed to indicate the desired graduated scale forming elements 16 depending upon a number of plates to be reproduced. The four indicators 17 shown in FIG. 2 are for indicating the units, tens, hundreds and thousands so that a four-digit number from 0001 to 9999 may be marked upon the plate.

Referring to FIG. 3, it is seen that the graduated scale forming elements 16 are placed in the same plane of the indicators 17 and both of the elements 16 and indicators 17 are spaced apart from the electrophotosensitive member by a relatively small distance. According to the present invention, the graduated scale forming elements 16 and the indicators 17 are projected upon the electrophoto-sensitive member by a light source different from that used for projecting the light image of the original upon the electrophoto-sensitive member.

Referring to FIG. 4, light is directed toward the elements l6 and the indicators 17 from a light source 21 so that their shadows may be also recorded upon the electrophoto-sensitive member in its unprinting portion, that is the portion which will not used for printing. The light source 21 and its optical path are shielded by a shield 22. According to the present invention, the shadow of the upstanding member 19 is not formed because the outermost beams of light from the light sources 21 and 7 intersect each other as shown in FIG. 4. In other words, the shadow of the upstanding member 19 is illuminated by the light from the light source 7 for projecting the light image of the original upon the electrophoto-sensitive member. However, the shadows of the elements 16 and the indicators 17 are recorded upon the electrophoto-sensitive member.

It is seen that the indicia consisting of the shadows of the graduated scale forming elements 16 and the indicators 17 may be recorded upon a predetermined portion of the electrophoto-sensitive member along with the image of the original irrespective its magnification. Furthermore, the dimensions of the indicia remain unchanged independent of the magnification or reduction of the original. Since the graduated scale forming elements 16 as well as the indicators 17 are arranged independently of the transparent original holder 9 upon which the dusts or the like tend to accumulate, the

shadows of the elements 16 and the indicators 17 may be clearly recorded upon the sensitized paper, so that the detection of the indicia is not adversely affected by the shadows of the dusts or the like which may produce the noise.

1f ii e lectrophotographic composing device including an exposure station (6) for exposing a plate and projecting means including a first light source (7) for projecting the image of an original onto a first portion of said plate when the plate is at the exposure station, wherein the improvement is in providing a device for recording upon a second portion of the plate indicia representing the number of copies to be printed by said plate, comprising a.- graduated scale forming elements (16) and a member (19) supporting said graduated scale forming elements at said exposure station (6) immediately above said second portion of a plate to be exposed, which second portion is not used in printing, said graduated scale-forming elements comprising opaque comb teeth spaced from the printing plate;

. opaque indicator means (17) slidably disposed in the same plane as that of said graduated scale forming elements (11) and actuable from the exterior of said composing device to indicate desired ones of said graduated scale forming elements to thereby represent the number of copies to be printed by the plate;

c. a second light source (21) for projecting the images of said graduated scale forming elements (16) and of said indicator means (17) upon said second portion of the plate, and

. means (22, 8, 10) for directing the beams of light from both of said first and second light source (7, 21) to intersect prior to impinging on said plate such that the beams from both of said first and second light source impinge on the portion of the plate immediately below said member (19) supporting said graduated scale forming elements and the image of said supporting member is not form ed upon the plate, but the images of the opaque comb teeth serving as graduated scale forming elements and of the opaque indicator means are formed on said second portion of the plate.

2. An electrophotographic composing device defined in claim 1 wherein said indicator means comprise tapered plates.

3. An electrophotographic composing device defined in claim 1 wherein each unit of said graduated scale forming elements comprises a group of ten combtooth-like members.

4. An electrophotographic composing device defined in claim 1 wherein numeral value in said each unit of said graduated scale forming elements is indicated by the position of said indicator fronting one of said combtooth-like members. 

1. An electrophotographic composing device including an exposure station (6) for exposing a plate and projecting means including a first light source (7) for projecting the image of an original onto a first portion of said plate when the plate is at the exposure station, wherein the improvement is in providing a device for recording upon a second portion of the plate indicia representing the number of copies to be printed by said plate, comprising a. graduated scale forming elements (16) and a member (19) supporting said graduated scale forming elements at said exposure station (6) immediately above said second portion of a plate to be exposed, which second portion is not used in printing, said graduated scale forming elements comprising opaque comb teeth spaced from the printing plate; b. opaque indicator means (17) slidably disposed in the same plane as that of said graduated scale forming elements (11) and actuable from the exterior of said composing device to indicate desired ones of said graduated scale forming elements to thereby represent the number of copies to be printed by the plate; c. a second light source (21) for projecting the images of said graduated scale forming elements (16) and of said indicator means (17) upon said second portion of the plate, and d. means (22, 8, 10) for directing the beams of light from both of said first and second light source (7, 21) to intersect prior to impinging on said plate such that the beams from both of said first and second light source impinge on the portion of the plate immediately below said member (19) supporting said graduated scale forming elements and the image of said supporting member is not formed upon the plate, but the images of the opaque comb teeth serving as graduated scale forming elements and of the opaque indicator means are formed on said second portion of the plate.
 2. An electrophotographic composing device defined in claim 1 wherein said indicator means comprise tapered plates.
 3. An electrophotographic composing device defined in claim 1 wherein each unit of said graduated scale forming elements comprises a group of ten comb-tooth-like members.
 4. An electrophotographic composing device defined in claim 1 wherein numeral value in said each unit of said graduated scale forming elements is indicated by the position of said indicator fronting one of said comb-tooth-like members. 